1. Modeling Atmospheric Deposition Across the Northeastern U.S. and its Potential Effects on Forest Albedo Danielle Haddad Scott V. Ollinger, Julian Jenkins, Mary Martin

2. Objectives Examine patterns of atmospheric deposition across the Northeast Region as a function of elevation and geographic location. Compare results with a 1993 model to quantify changes in the last 16 years since the earlier model was created. Use the new equations within a GIS to create maps of atmospheric deposition. Test a recent hypothesis that nitrogen deposition may have an influence on mid-summer albedo in forests. Ollinger et al. 1993

3. Sites NADP sites (National Atmospheric Deposition Program sites) CASTNET sites (Clean Air Status and Trends Network sites)

4. Trends in Wet Deposition Longitude trends reflect long distance pollution transport from industrial activity in the Great Lakes region.

5. Trends in Dry Deposition Latitude trends reflect more local pollution sources, the concentration of urban areas along the southern portions of the region.

6. Changes in Wet Deposition Over Time The wet deposition of NO3 and SO4 have decreased over time, due to amendments made to the Clean Air Act in 1990. NH4 deposition, which comes mainly from agriculture, has remained unchanged.

7. Changes in Dry Deposition Over Time The dry deposition of SO2, SO4, HNO3, and NH4 have decreased over time, most likely still due to amendments made to the Clean Air Act in 1990.

8. Final Model with Time as a Continuous Variable

9. Estimated Deposition in 1990 and 2008

10. Ollinger et al. 2008 (PNAS) found that canopy nitrogen in N. American Forests was strongly related to total shortwave albedo. This raises the question of whether nitrogen deposition and other factors that can alter canopy %N might also have an effect on albedo. To test this, we compared remotely sensed albedo from MODIS with estimated N deposition from the new model. Does Nitrogen Deposition Alter the Albedo of Forests?

11. Spatial Data Layers used in the Albedo-N Deposition Comparison MODIS Land Cover (Friedl et al. 2002) Mid-Summer Shortwave Albedo (Schaff et al. 2002) Percent Tree Cover (Hansen et al. 2003) < 38 38 - 68 68 - 93 93 - 112 112 - 125 125 - 135 135 - 144 144 - 154 >154 0 - 70 > 70

12. Albedo vs. Nitrogen Deposition in Deciduous Forest This suggests N deposition has an effect on climate through alteration of canopy reflectance and surface heating.

13. NASA Connections With further studies, we may be able to estimate nitrogen concentration from space using shortwave albedo and use the information to more accurately model CO2 uptake and surface energy exchange by terrestrial ecosystems. Ollinger et al. 2008 (PNAS)

14. Sources Deposition Program/ National Trends Network (NADP/NTN) http://nadp.sws.uiuc.edu/http://nadp.sws.uiuc.edu/ Clean Air Status and Trends Network (CASTNET) http://www.epa.gov/castnet/http://www.epa.gov/castnet/ NOAA's National Climatic Data Center (NCDC), United States Climate Normals 1971-2000 http://lwf.ncdc.noaa.gov/oa/climate/normals/usnormals.html http://lwf.ncdc.noaa.gov/oa/climate/normals/usnormals.html GPS Visualizer: Assign elevation data to coordinates, Adam Schneider 2003 -2009, http://www.gpsvisualizer.com/elevation http://www.gpsvisualizer.com/elevation MOD43C1 V004 Modis Albedo 16-Day L3 Global 0.05 Degree CMG Binary Data Sets, Boston University Department of Geography, updated 11 Jan 2007, http://www- modis.bu.edu/brdf_albedo/albedo16/http://www- modis.bu.edu/brdf_albedo/albedo16/ MOD12C1 Land Cover Product Binary Data, Boston University Department of Geography, updated 26 Sep 2005, http://duckwater.bu.edu/duckwater1/mod12c1/index.htmlhttp://duckwater.bu.edu/duckwater1/mod12c1/index.html Global Land Cover Facility, University of Maryland, 1997, http://glcf.umiacs.umd.edu/index.shtmlhttp://glcf.umiacs.umd.edu/index.shtml Scott V. Ollinger, John D. Aber, Gary M. Lovett, Sarah E. Millham, Richard G. Lathrop, and Jennifer M. Ellis. 1993. A Spatial Model Of Atmospheric Deposition For The Northeastern U.S..Ecological Applications, 3(3), pp. 459-472. Scott V. Ollinger, John D. Aber, Anthony Federer, Gary M. Lovett, and Jennifer M. Ellis. 1995. Modeling Physical and Chemical Climate of the Northeastern United States for a Geographic Information System. Department of Agriculture, Forest Service, General Technical Report NE- 191. Radnor PA 19087-8775. S. V. Ollinger, A. D. Richardson, M. E. Martin, D. Y. Hollinger, S. E. Frolking, P. B. Reich, L. C. Plourde, G. G. Katul, J. W. Munger, R. Oren, M. L. Smith, K. T. Paw U, P. V. Bolstad, B. D. Cook, M. C. Day, T. A. Martin, R. K. Monson, and H. P. Schmid. 2008. Canopy nitrogen, carbon assimilation, and albedo in temperate and boreal forests: Functional relations and potential climate feedbacks. PNAS, vol. 105, no. 49, pp. 19335-19340. James A. Lynch, Van C. Bowersox, Jeffrey W. Grimm. 2000. Acid Rain Reduced in Eastern United States. Environmental Science & Technology, vol. 34, no. 6, pp. 940-948. Charles T. Driscoll, Gregory B. Lawrence, Arthur J. Bulger, Thomas J. Butler, Christopher S. Cronan, Christopher Eagar, Kathleen F. Lambert, Gene E. Likens, John L. Stoddard, and Kathleen C. Weathers. 2001. Acidic Deposition in the Northeastern United States: Sources and Inputs, Ecosystem Effects, and Management Strategies. BioScience, vol. 51, no. 3, pp. 180-198.